linux.git/drivers/dma/pl330.c, branch v3.19 Linux kernel source tree Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm 2014-12-12T23:26:48+00:00 Linus Torvalds torvalds@linux-foundation.org 2014-12-12T23:26:48+00:00 26ceb127f7bcf473db926c6a026b18ddd6f274e8 Pull ARM updates from Russell King: "The major updates included in this update are: - Clang compatible stack pointer accesses by Behan Webster. - SA11x0 updates from Dmitry Eremin-Solenikov. - kgdb handling of breakpoints with read-only text/modules - Support for Privileged-no-execute feature on ARMv7 to prevent userspace code execution by the kernel. - AMBA primecell bus handling of irq-safe runtime PM - Unwinding support for memset/memzero/memmove/memcpy functions - VFP fixes for Krait CPUs and improvements in detecting the VFP architecture - A number of code cleanups (using pr_*, removing or reducing the severity of a couple of kernel messages, splitting ftrace asm code out to a separate file, etc.) - Add machine name to stack dump output" * 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (62 commits) ARM: 8247/2: pcmcia: sa1100: make use of device clock ARM: 8246/2: pcmcia: sa1111: provide device clock ARM: 8245/1: pcmcia: soc-common: enable/disable socket clocks ARM: 8244/1: fbdev: sa1100fb: make use of device clock ARM: 8243/1: sa1100: add a clock alias for sa1111 pcmcia device ARM: 8242/1: sa1100: add cpu clock ARM: 8221/1: PJ4: allow building in Thumb-2 mode ARM: 8234/1: sa1100: reorder IRQ handling code ARM: 8233/1: sa1100: switch to hwirq usage ARM: 8232/1: sa1100: merge GPIO multiplexer IRQ to "normal" irq domain ARM: 8231/1: sa1100: introduce irqdomains support ARM: 8230/1: sa1100: shift IRQs by one ARM: 8229/1: sa1100: replace irq numbers with names in irq driver ARM: 8228/1: sa1100: drop entry-macro.S ARM: 8227/1: sa1100: switch to MULTI_IRQ_HANDLER ARM: 8241/1: Update processor_modes for hyp and monitor mode ARM: 8240/1: MCPM: document mcpm_sync_init() ARM: 8239/1: Introduce {set,clear}_pte_bit ARM: 8238/1: mm: Refine set_memory_* functions ARM: 8237/1: fix flush_pfn_alias ... 
Pull ARM updates from Russell King:
 "The major updates included in this update are:

   - Clang compatible stack pointer accesses by Behan Webster.
   - SA11x0 updates from Dmitry Eremin-Solenikov.
   - kgdb handling of breakpoints with read-only text/modules
   - Support for Privileged-no-execute feature on ARMv7 to prevent
     userspace code execution by the kernel.
   - AMBA primecell bus handling of irq-safe runtime PM
   - Unwinding support for memset/memzero/memmove/memcpy functions
   - VFP fixes for Krait CPUs and improvements in detecting the VFP
     architecture
   - A number of code cleanups (using pr_*, removing or reducing the
     severity of a couple of kernel messages, splitting ftrace asm code
     out to a separate file, etc.)
   - Add machine name to stack dump output"

* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (62 commits)
  ARM: 8247/2: pcmcia: sa1100: make use of device clock
  ARM: 8246/2: pcmcia: sa1111: provide device clock
  ARM: 8245/1: pcmcia: soc-common: enable/disable socket clocks
  ARM: 8244/1: fbdev: sa1100fb: make use of device clock
  ARM: 8243/1: sa1100: add a clock alias for sa1111 pcmcia device
  ARM: 8242/1: sa1100: add cpu clock
  ARM: 8221/1: PJ4: allow building in Thumb-2 mode
  ARM: 8234/1: sa1100: reorder IRQ handling code
  ARM: 8233/1: sa1100: switch to hwirq usage
  ARM: 8232/1: sa1100: merge GPIO multiplexer IRQ to "normal" irq domain
  ARM: 8231/1: sa1100: introduce irqdomains support
  ARM: 8230/1: sa1100: shift IRQs by one
  ARM: 8229/1: sa1100: replace irq numbers with names in irq driver
  ARM: 8228/1: sa1100: drop entry-macro.S
  ARM: 8227/1: sa1100: switch to MULTI_IRQ_HANDLER
  ARM: 8241/1: Update processor_modes for hyp and monitor mode
  ARM: 8240/1: MCPM: document mcpm_sync_init()
  ARM: 8239/1: Introduce {set,clear}_pte_bit
  ARM: 8238/1: mm: Refine set_memory_* functions
  ARM: 8237/1: fix flush_pfn_alias
  ...
Merge branch 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma 2014-12-12T22:59:53+00:00 Linus Torvalds torvalds@linux-foundation.org 2014-12-12T22:59:53+00:00 87c779baabff157f09db6fce417a7544220f9f00 Pull dmaengine updates from Vinod Koul: "Main features this time are: - BAM v1.3.0 support form qcom bam dma - support for Allwinner sun8i dma - atmels eXtended DMA Controller driver - chancnt cleanup by Maxime - fixes spread over drivers" * 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma: (56 commits) dmaenegine: Delete a check before free_percpu() dmaengine: ioatdma: fix dma mapping errors dma: cppi41: add a delay while setting the TD bit dma: cppi41: wait longer for the HW to return the descriptor dmaengine: fsl-edma: fixup reg offset and hw S/G support in big-endian model dmaengine: fsl-edma: fix calculation of remaining bytes drivers/dma/pch_dma: declare pch_dma_id_table as static dmaengine: ste_dma40: fix error return code dma: imx-sdma: clarify about firmware not found error Documentation: devicetree: Fix Xilinx VDMA specification dmaengine: pl330: update author info dmaengine: clarify the issue_pending expectations dmaengine: at_xdmac: Add DMA_PRIVATE ARM: dts: at_xdmac: fix bad value of dma-cells in documentation dmaengine: at_xdmac: fix missing spin_unlock dmaengine: at_xdmac: fix a bug in transfer residue computation dmaengine: at_xdmac: fix software lockup at_xdmac_tx_status() dmaengine: at_xdmac: remove chancnt affectation dmaengine: at_xdmac: prefer usage of readl/writel_relaxed dmaengine: xdmac: fix print warning on dma_addr_t variable ... 
Pull dmaengine updates from Vinod Koul:
 "Main features this time are:

   - BAM v1.3.0 support form qcom bam dma
   - support for Allwinner sun8i dma
   - atmels eXtended DMA Controller driver
   - chancnt cleanup by Maxime
   - fixes spread over drivers"

* 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma: (56 commits)
  dmaenegine: Delete a check before free_percpu()
  dmaengine: ioatdma: fix dma mapping errors
  dma: cppi41: add a delay while setting the TD bit
  dma: cppi41: wait longer for the HW to return the descriptor
  dmaengine: fsl-edma: fixup reg offset and hw S/G support in big-endian model
  dmaengine: fsl-edma: fix calculation of remaining bytes
  drivers/dma/pch_dma: declare pch_dma_id_table as static
  dmaengine: ste_dma40: fix error return code
  dma: imx-sdma: clarify about firmware not found error
  Documentation: devicetree: Fix Xilinx VDMA specification
  dmaengine: pl330: update author info
  dmaengine: clarify the issue_pending expectations
  dmaengine: at_xdmac: Add DMA_PRIVATE
  ARM: dts: at_xdmac: fix bad value of dma-cells in documentation
  dmaengine: at_xdmac: fix missing spin_unlock
  dmaengine: at_xdmac: fix a bug in transfer residue computation
  dmaengine: at_xdmac: fix software lockup at_xdmac_tx_status()
  dmaengine: at_xdmac: remove chancnt affectation
  dmaengine: at_xdmac: prefer usage of readl/writel_relaxed
  dmaengine: xdmac: fix print warning on dma_addr_t variable
  ...
dmaengine: pl330: update author info 2014-12-05T15:34:22+00:00 Jassi Brar jassisinghbrar@gmail.com 2014-12-05T13:37:49+00:00 046209f61b5f35fa08a9e76ce678ad0f3ca8a417 Update email-id to a personal one, as I have changed employment. Signed-off-by: Jassi Brar <jassisinghbrar@gmail.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com> 
Update email-id to a personal one, as I have changed employment.

Signed-off-by: Jassi Brar <jassisinghbrar@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
ARM: 8206/1: dmaengine: pl330: Add PM sleep support 2014-11-27T16:13:08+00:00 Krzysztof Kozlowski k.kozlowski@samsung.com 2014-11-18T11:17:56+00:00 b816ccc5c01fb7fe1fb001ff7aa5aa7e5a8aa76b Add system suspend/resume capabilities to the pl330 driver so the amba bus clock could be also unprepared to conserve energy. Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
Add system suspend/resume capabilities to the pl330 driver so the amba
bus clock could be also unprepared to conserve energy.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: 8202/1: dmaengine: pl330: Add runtime Power Management support v12 2014-11-17T20:23:36+00:00 Krzysztof Kozlowski k.kozlowski@samsung.com 2014-11-14T08:48:57+00:00 ae43b3289186480f81c78bb63d788a85a3631f47 This patch adds runtime PM support to pl330 DMA engine driver. The runtime power management for pl330 DMA driver allows gating of AMBA clock (PDMA) in FSYS clock domain, when the device is not processing any requests. This is necessary to enter low power modes on Exynos SoCs (e.g. LPA on Exynos4x12 or W-AFTR on Exynos3250). Runtime PM resuming of the device may happen in atomic context (during call device_issue_pending()) so pm_runtime_irq_safe() is used. This will lead only to disabling/enabling of the clock but this is sufficient for gating the clock and for reducing energy usage. Driver uses runtime PM callbacks from amba/bus.c driver only. Suggested-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Vinod Koul <vinod.koul@intel.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
This patch adds runtime PM support to pl330 DMA engine driver.

The runtime power management for pl330 DMA driver allows gating of AMBA
clock (PDMA) in FSYS clock domain, when the device is not processing any
requests. This is necessary to enter low power modes on Exynos SoCs
(e.g. LPA on Exynos4x12 or W-AFTR on Exynos3250).

Runtime PM resuming of the device may happen in atomic context (during
call device_issue_pending()) so pm_runtime_irq_safe() is used. This will
lead only to disabling/enabling of the clock but this is sufficient for
gating the clock and for reducing energy usage.

Driver uses runtime PM callbacks from amba/bus.c driver only.

Suggested-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
dmaengine: pl330: Correct device assignment. 2014-11-17T08:20:34+00:00 Andrew Jackson Andrew.Jackson@arm.com 2014-11-06T11:39:47+00:00 cee42392f5f0482d5cc71635a9c57b4ccdadb886 Commit f6f2421c0a1c removed pl330_info structure by embedding it into pl330_dmac structure, but did not ensure that the dmac->ddma.dev pointer gets initialised before use. When dma_alloc_coherent() gets called on arm64 a WARN() gets triggered due to dev being NULL. ------------[ cut here ]------------ WARNING: CPU: 1 PID: 1 at arch/arm64/mm/dma-mapping.c:49 __dma_alloc_coherent+0xd0/0xe0() Use an actual device structure for DMA allocation Modules linked in: CPU: 1 PID: 1 Comm: swapper/0 Not tainted 3.17.0+ #5 Call trace: [<ffffffc000087f24>] dump_backtrace+0x0/0x130 [<ffffffc000088064>] show_stack+0x10/0x1c [<ffffffc0004e8af8>] dump_stack+0x74/0xb8 [<ffffffc0000aa444>] warn_slowpath_common+0x8c/0xb4 [<ffffffc0000aa4b8>] warn_slowpath_fmt+0x4c/0x58 [<ffffffc000092580>] __dma_alloc_coherent+0xcc/0xe0 [<ffffffc000092734>] __dma_alloc_noncoherent+0x64/0x158 [<ffffffc000312cd8>] pl330_probe+0x650/0x8f0 [<ffffffc00030e1d4>] amba_probe+0xa0/0xc8 [<ffffffc000350240>] really_probe+0xc4/0x22c [<ffffffc0003504b4>] __driver_attach+0xa0/0xa8 [<ffffffc00034e5fc>] bus_for_each_dev+0x54/0x98 [<ffffffc00034fd8c>] driver_attach+0x1c/0x28 [<ffffffc00034fa08>] bus_add_driver+0x14c/0x204 [<ffffffc000350b84>] driver_register+0x64/0x130 [<ffffffc00030dcf8>] amba_driver_register+0x50/0x5c [<ffffffc0006a60d0>] pl330_driver_init+0x10/0x1c [<ffffffc0000814ac>] do_one_initcall+0x88/0x19c [<ffffffc00068dab8>] kernel_init_freeable+0x140/0x1e0 [<ffffffc0004e5e18>] kernel_init+0x10/0xd4 ---[ end trace 76f2d47a444e523e ]--- (NULL device *): dmac_alloc_resources:1821 Can't allocate memory! (NULL device *): Unable to create channels for DMAC This patch will also ensure that any dev_err messages are printed with the appropriate device name. Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com> Signed-off-by: Andrew Jackson <Andrew.Jackson@arm.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com> 
Commit f6f2421c0a1c removed pl330_info structure by embedding it into
pl330_dmac structure, but did not ensure that the dmac->ddma.dev
pointer gets initialised before use. When dma_alloc_coherent() gets
called on arm64 a WARN() gets triggered due to dev being NULL.

------------[ cut here ]------------
WARNING: CPU: 1 PID: 1 at arch/arm64/mm/dma-mapping.c:49 __dma_alloc_coherent+0xd0/0xe0()
Use an actual device structure for DMA allocation
Modules linked in:
CPU: 1 PID: 1 Comm: swapper/0 Not tainted 3.17.0+ #5
Call trace:
[<ffffffc000087f24>] dump_backtrace+0x0/0x130
[<ffffffc000088064>] show_stack+0x10/0x1c
[<ffffffc0004e8af8>] dump_stack+0x74/0xb8
[<ffffffc0000aa444>] warn_slowpath_common+0x8c/0xb4
[<ffffffc0000aa4b8>] warn_slowpath_fmt+0x4c/0x58
[<ffffffc000092580>] __dma_alloc_coherent+0xcc/0xe0
[<ffffffc000092734>] __dma_alloc_noncoherent+0x64/0x158
[<ffffffc000312cd8>] pl330_probe+0x650/0x8f0
[<ffffffc00030e1d4>] amba_probe+0xa0/0xc8
[<ffffffc000350240>] really_probe+0xc4/0x22c
[<ffffffc0003504b4>] __driver_attach+0xa0/0xa8
[<ffffffc00034e5fc>] bus_for_each_dev+0x54/0x98
[<ffffffc00034fd8c>] driver_attach+0x1c/0x28
[<ffffffc00034fa08>] bus_add_driver+0x14c/0x204
[<ffffffc000350b84>] driver_register+0x64/0x130
[<ffffffc00030dcf8>] amba_driver_register+0x50/0x5c
[<ffffffc0006a60d0>] pl330_driver_init+0x10/0x1c
[<ffffffc0000814ac>] do_one_initcall+0x88/0x19c
[<ffffffc00068dab8>] kernel_init_freeable+0x140/0x1e0
[<ffffffc0004e5e18>] kernel_init+0x10/0xd4
---[ end trace 76f2d47a444e523e ]---
(NULL device *): dmac_alloc_resources:1821 Can't allocate memory!
(NULL device *): Unable to create channels for DMAC

This patch will also ensure that any dev_err messages are printed
with the appropriate device name.

Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Andrew Jackson <Andrew.Jackson@arm.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
dmaengine: Fix allocation size for PL330 data buffer depth. 2014-11-17T07:31:22+00:00 Liviu Dudau Liviu.Dudau@arm.com 2014-11-06T17:20:12+00:00 1f0a5cbf61a54504236bbbe2c98b58e85f90e650 The datasheet for PL330 says that the data buffer value in the CRD register is 10bits wide. However, the value stored is "minus one", which the driver corrects for. Maximum value that the data buffer depth can have is 1024 lines, which requires 11 bits for storage. While making updates I found printing the peripheral ID as a hex value to be more useful as the datasheet shows the values that way. Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com> 
The datasheet for PL330 says that the data buffer value in the CRD
register is 10bits wide. However, the value stored is "minus one",
which the driver corrects for. Maximum value that the data buffer
depth can have is 1024 lines, which requires 11 bits for storage.

While making updates I found printing the peripheral ID as a hex
value to be more useful as the datasheet shows the values that way.

Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
dmaengine: pl330: Limit MFIFO usage for memcpy to avoid exhausting entries 2014-11-17T07:31:20+00:00 Jon Medhurst tixy@linaro.org 2014-11-07T18:05:18+00:00 c27f95568d1ed2573fc9c8848d741da63ca9a34e The MFIFO is shared by all channels so restrict each memcpy to it's fair share. This is being over cautious, but without a global view of DMA channel usage on a system it's not possible to come up with a more optimum safe limit. Signed-off-by: Jon Medhurst <tixy@linaro.org> Signed-off-by: Vinod Koul <vinod.koul@intel.com> 
The MFIFO is shared by all channels so restrict each memcpy to it's fair
share. This is being over cautious, but without a global view of DMA
channel usage on a system it's not possible to come up with a more
optimum safe limit.

Signed-off-by: Jon Medhurst <tixy@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
dmaengine: pl330: Align DMA memcpy operations to MFIFO width 2014-11-17T07:31:09+00:00 Jon Medhurst tixy@linaro.org 2014-11-07T18:05:17+00:00 137bd11090d89b3a3ef4bdb7a6cf964ffc797517 The algorithm used for programming the DMA Controller doesn't take into consideration the requirements of transfers that are not aligned to the bus width. This failure may result in DMA transferring one too few MFIFO entries (so too few bytes are copied) or the DMA trying to write one too many MFIFO entries and hanging because this is never provided. See "MFIFO Usage Overview" chapter in the the TRM for "CoreLink DMA Controller DMA-330", Revision r1p1. We work around these shortcomings by making sure we pick a burst size and length which ensures no bursts straddle an MFIFO entry. Signed-off-by: Jon Medhurst <tixy@linaro.org> [squashed linker error "undefined reference to `__aeabi_uldivmod] Reported-by: kbuild test robot <fengguang.wu@intel.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Vinod Koul <vinod.koul@intel.com> 
The algorithm used for programming the DMA Controller doesn't take into
consideration the requirements of transfers that are not aligned to the
bus width. This failure may result in DMA transferring one too few MFIFO
entries (so too few bytes are copied) or the DMA trying to write one too
many MFIFO entries and hanging because this is never provided.

See "MFIFO Usage Overview" chapter in the the TRM for "CoreLink DMA
Controller DMA-330", Revision r1p1.

We work around these shortcomings by making sure we pick a burst size
and length which ensures no bursts straddle an MFIFO entry.

Signed-off-by: Jon Medhurst <tixy@linaro.org>
[squashed linker error "undefined reference to `__aeabi_uldivmod]
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
dmaengine: pl330: Fix NULL pointer dereference on driver unbind 2014-10-15T08:00:09+00:00 Krzysztof Kozlowski k.kozlowski@samsung.com 2014-09-29T12:42:21+00:00 6e4a2a83f95826201bbd89f55522537ea52d1d67 Fix a NULL pointer dereference after unbinding the driver, if channel resources were not yet allocated (no call to pl330_alloc_chan_resources()): $ echo 12850000.mdma > /sys/bus/amba/drivers/dma-pl330/unbind [ 13.606533] DMA pl330_control: removing pch: eeab6800, chan: eeab6814, thread: (null) [ 13.614472] Unable to handle kernel NULL pointer dereference at virtual address 0000000c [ 13.622537] pgd = ee284000 [ 13.625228] [0000000c] *pgd=6e1e4831, *pte=00000000, *ppte=00000000 [ 13.631482] Internal error: Oops: 17 [#1] PREEMPT SMP ARM [ 13.636859] Modules linked in: [ 13.639903] CPU: 0 PID: 1 Comm: sh Not tainted 3.17.0-rc3-next-20140904-00004-g7020ffc33ca3-dirty #420 [ 13.649187] task: ee80a800 ti: ee888000 task.ti: ee888000 [ 13.654589] PC is at _stop+0x8/0x2c8 [ 13.658131] LR is at pl330_control+0x70/0x2e8 [ 13.662468] pc : [<c0206028>] lr : [<c020649c>] psr: 60000093 [ 13.662468] sp : ee889e58 ip : 00000001 fp : 000bab70 [ 13.673922] r10: eeab6814 r9 : ee16debc r8 : 00000000 [ 13.679131] r7 : eeab685c r6 : 60000013 r5 : ee16de10 r4 : eeab6800 [ 13.685641] r3 : 00000002 r2 : 00000000 r1 : 00010000 r0 : 00000000 [ 13.692153] Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment user [ 13.699357] Control: 10c5387d Table: 6e28404a DAC: 00000015 [ 13.705085] Process sh (pid: 1, stack limit = 0xee888240) [ 13.710466] Stack: (0xee889e58 to 0xee88a000) [ 13.714808] 9e40: 00000002 eeab6800 [ 13.722969] 9e60: ee16de10 eeab6800 ee16de10 60000013 eeab685c c020649c 00000000 c040280c [ 13.731128] 9e80: ee889e80 ee889e80 ee16de18 ee16de10 eeab6880 eeab6814 00200200 eeab68a8 [ 13.739287] 9ea0: 00100100 c0208048 00000000 c0409fc4 eea80800 eea808f8 c0605c44 0000000e [ 13.747446] 9ec0: 0000000e eeb3960c eeb39600 c0203c48 eea80800 c0605c44 c0605a8c c023f694 [ 13.755605] 9ee0: ee80a800 eea80834 eea80800 c023f704 ee80a800 eea80800 c0605c44 c023e8ec [ 13.763764] 9f00: 0000000e ee149780 ee29e580 ee889f80 ee29e580 c023e19c 0000000e c01167e4 [ 13.771923] 9f20: c01167a0 00000000 00000000 c0115e88 00000000 00000000 ee0b1a00 0000000e [ 13.780082] 9f40: b6f48000 ee889f80 0000000e ee888000 b6f48000 c00bfadc 00000000 00000003 [ 13.788241] 9f60: 00000000 00000000 00000000 ee0b1a00 ee0b1a00 0000000e b6f48000 c00bfdf4 [ 13.796401] 9f80: 00000000 00000000 ffffffff 0000000e b6f48000 b6edc5d0 00000004 c000e7a4 [ 13.804560] 9fa0: 00000000 c000e620 0000000e b6f48000 00000001 b6f48000 0000000e 00000000 [ 13.812719] 9fc0: 0000000e b6f48000 b6edc5d0 00000004 0000000e b6f4c8c0 000c3470 000bab70 [ 13.820879] 9fe0: 00000000 bed2aa50 b6e18bdc b6e6b52c 60000010 00000001 c0c0c0c0 c0c0c0c0 [ 13.829058] [<c0206028>] (_stop) from [<c020649c>] (pl330_control+0x70/0x2e8) [ 13.836165] [<c020649c>] (pl330_control) from [<c0208048>] (pl330_remove+0xb0/0xdc) [ 13.843800] [<c0208048>] (pl330_remove) from [<c0203c48>] (amba_remove+0x24/0xc0) [ 13.851272] [<c0203c48>] (amba_remove) from [<c023f694>] (__device_release_driver+0x70/0xc4) [ 13.859685] [<c023f694>] (__device_release_driver) from [<c023f704>] (device_release_driver+0x1c/0x28) [ 13.868971] [<c023f704>] (device_release_driver) from [<c023e8ec>] (unbind_store+0x58/0x90) [ 13.877303] [<c023e8ec>] (unbind_store) from [<c023e19c>] (drv_attr_store+0x20/0x2c) [ 13.885036] [<c023e19c>] (drv_attr_store) from [<c01167e4>] (sysfs_kf_write+0x44/0x48) [ 13.892928] [<c01167e4>] (sysfs_kf_write) from [<c0115e88>] (kernfs_fop_write+0xc0/0x17c) [ 13.901090] [<c0115e88>] (kernfs_fop_write) from [<c00bfadc>] (vfs_write+0xa0/0x1a8) [ 13.908812] [<c00bfadc>] (vfs_write) from [<c00bfdf4>] (SyS_write+0x40/0x8c) [ 13.915850] [<c00bfdf4>] (SyS_write) from [<c000e620>] (ret_fast_syscall+0x0/0x30) [ 13.923392] Code: e5813010 e12fff1e e92d40f0 e24dd00c (e590200c) [ 13.929467] ---[ end trace 10064e15a5929cf8 ]--- Terminate the thread and free channel resource only if channel resources were allocated (thread is not NULL). Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Cc: <stable@vger.kernel.org> Fixes: b3040e40675e ("DMA: PL330: Add dma api driver") Reviewed-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Vinod Koul <vinod.koul@intel.com> 
Fix a NULL pointer dereference after unbinding the driver, if channel
resources were not yet allocated (no call to
pl330_alloc_chan_resources()):
$ echo 12850000.mdma > /sys/bus/amba/drivers/dma-pl330/unbind
[   13.606533] DMA pl330_control: removing pch: eeab6800, chan: eeab6814, thread:   (null)
[   13.614472] Unable to handle kernel NULL pointer dereference at virtual address 0000000c
[   13.622537] pgd = ee284000
[   13.625228] [0000000c] *pgd=6e1e4831, *pte=00000000, *ppte=00000000
[   13.631482] Internal error: Oops: 17 [#1] PREEMPT SMP ARM
[   13.636859] Modules linked in:
[   13.639903] CPU: 0 PID: 1 Comm: sh Not tainted 3.17.0-rc3-next-20140904-00004-g7020ffc33ca3-dirty #420
[   13.649187] task: ee80a800 ti: ee888000 task.ti: ee888000
[   13.654589] PC is at _stop+0x8/0x2c8
[   13.658131] LR is at pl330_control+0x70/0x2e8
[   13.662468] pc : [<c0206028>]    lr : [<c020649c>]    psr: 60000093
[   13.662468] sp : ee889e58  ip : 00000001  fp : 000bab70
[   13.673922] r10: eeab6814  r9 : ee16debc  r8 : 00000000
[   13.679131] r7 : eeab685c  r6 : 60000013  r5 : ee16de10  r4 : eeab6800
[   13.685641] r3 : 00000002  r2 : 00000000  r1 : 00010000  r0 : 00000000
[   13.692153] Flags: nZCv  IRQs off  FIQs on  Mode SVC_32  ISA ARM  Segment user
[   13.699357] Control: 10c5387d  Table: 6e28404a  DAC: 00000015
[   13.705085] Process sh (pid: 1, stack limit = 0xee888240)
[   13.710466] Stack: (0xee889e58 to 0xee88a000)
[   13.714808] 9e40:                                                       00000002 eeab6800
[   13.722969] 9e60: ee16de10 eeab6800 ee16de10 60000013 eeab685c c020649c 00000000 c040280c
[   13.731128] 9e80: ee889e80 ee889e80 ee16de18 ee16de10 eeab6880 eeab6814 00200200 eeab68a8
[   13.739287] 9ea0: 00100100 c0208048 00000000 c0409fc4 eea80800 eea808f8 c0605c44 0000000e
[   13.747446] 9ec0: 0000000e eeb3960c eeb39600 c0203c48 eea80800 c0605c44 c0605a8c c023f694
[   13.755605] 9ee0: ee80a800 eea80834 eea80800 c023f704 ee80a800 eea80800 c0605c44 c023e8ec
[   13.763764] 9f00: 0000000e ee149780 ee29e580 ee889f80 ee29e580 c023e19c 0000000e c01167e4
[   13.771923] 9f20: c01167a0 00000000 00000000 c0115e88 00000000 00000000 ee0b1a00 0000000e
[   13.780082] 9f40: b6f48000 ee889f80 0000000e ee888000 b6f48000 c00bfadc 00000000 00000003
[   13.788241] 9f60: 00000000 00000000 00000000 ee0b1a00 ee0b1a00 0000000e b6f48000 c00bfdf4
[   13.796401] 9f80: 00000000 00000000 ffffffff 0000000e b6f48000 b6edc5d0 00000004 c000e7a4
[   13.804560] 9fa0: 00000000 c000e620 0000000e b6f48000 00000001 b6f48000 0000000e 00000000
[   13.812719] 9fc0: 0000000e b6f48000 b6edc5d0 00000004 0000000e b6f4c8c0 000c3470 000bab70
[   13.820879] 9fe0: 00000000 bed2aa50 b6e18bdc b6e6b52c 60000010 00000001 c0c0c0c0 c0c0c0c0
[   13.829058] [<c0206028>] (_stop) from [<c020649c>] (pl330_control+0x70/0x2e8)
[   13.836165] [<c020649c>] (pl330_control) from [<c0208048>] (pl330_remove+0xb0/0xdc)
[   13.843800] [<c0208048>] (pl330_remove) from [<c0203c48>] (amba_remove+0x24/0xc0)
[   13.851272] [<c0203c48>] (amba_remove) from [<c023f694>] (__device_release_driver+0x70/0xc4)
[   13.859685] [<c023f694>] (__device_release_driver) from [<c023f704>] (device_release_driver+0x1c/0x28)
[   13.868971] [<c023f704>] (device_release_driver) from [<c023e8ec>] (unbind_store+0x58/0x90)
[   13.877303] [<c023e8ec>] (unbind_store) from [<c023e19c>] (drv_attr_store+0x20/0x2c)
[   13.885036] [<c023e19c>] (drv_attr_store) from [<c01167e4>] (sysfs_kf_write+0x44/0x48)
[   13.892928] [<c01167e4>] (sysfs_kf_write) from [<c0115e88>] (kernfs_fop_write+0xc0/0x17c)
[   13.901090] [<c0115e88>] (kernfs_fop_write) from [<c00bfadc>] (vfs_write+0xa0/0x1a8)
[   13.908812] [<c00bfadc>] (vfs_write) from [<c00bfdf4>] (SyS_write+0x40/0x8c)
[   13.915850] [<c00bfdf4>] (SyS_write) from [<c000e620>] (ret_fast_syscall+0x0/0x30)
[   13.923392] Code: e5813010 e12fff1e e92d40f0 e24dd00c (e590200c)
[   13.929467] ---[ end trace 10064e15a5929cf8 ]---

Terminate the thread and free channel resource only if channel resources
were allocated (thread is not NULL).

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: <stable@vger.kernel.org>
Fixes: b3040e40675e ("DMA: PL330: Add dma api driver")
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>